1. Field of the Invention
The present invention relates to the field of roofing, and more particulrly, non-metallic roofing such as asphalt composition and woodshake roofing.
2. Prior Art
Asphalt composition roofing of various types is very well known in the prior art. Such materials are characterized by a base layer of felt-like material, saturated with asphalt, and having a layer of asphalt on one surface thereof binding an outer layer of granules thereto. Such materials are relatively inexpensive and of light weight, thereby finding wide usage, though historically have been characterized as providing a relatively flat (i.e. non-three dimensional) roof, thereby having a minimal decorative character. Also, asphalt composition roofing, whether by way of conventional shingles or otherwise, has historically utilized a highly repetitive pattern in the roofing, thereby again limiting the decorative characteristic of the roof.
In certain instances in the prior art, asphalt composition materials had been folded for various purposes, including folding to provide improved sealing characteristics and folding to create regions of increased thickness to provide some better three-dimensional characteristic. Such folding however, was in general limited, with the resulting roof again having the highly repetitive design generally characteristic of asphalt composition roofs. Examples of such folding may be found in U.S. Pats. No. 1,410,299; 1,435,623; 1,596,272; 1,848,965; 1,975,986; and 2,253,753. In U.S. Pat. No. 3,913,294 an asphalt composition hip and ridge cover giving a highly pronounced three-dimensional characteristic is disclosed, this ridge cover providing a building silloutte resembling that of a building with a shake roof. Shingles of a similar character however, have heretofore not been known, except for the general type of shingle or shingle-like roofing exemplified by the foregoing prior art. In recent years, to enhance the appearance of asphalt composition shingles, various techniques have been used, including the use of varying thicknesses of the asphalt layer over the base material to provide variation in the shingle thicknesses, and use of a different color granule on the lower portion of the shingle to provide a shading effect to provide the illusion of a deeper three-dimensional roof.